KVM: s390: add kvm to kconfig on s390

This patch adds the virtualization submenu and the kvm option to the kernel
config. It also defines HAVE_KVM for 64bit kernels.

Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>

arch/s390/Kconfig

@@ -73,6 +73,7 @@ config S390
 	select HAVE_OPROFILE
 	select HAVE_KPROBES
 	select HAVE_KRETPROBES
+	select HAVE_KVM if 64BIT
 
 source "init/Kconfig"
 
@@ -540,3 +541,5 @@ source "security/Kconfig"
 source "crypto/Kconfig"
 
 source "lib/Kconfig"
+
+source "arch/s390/kvm/Kconfig"

arch/s390/kvm/Kconfig

+#
+# KVM configuration
+#
+config HAVE_KVM
+       bool
+
+menuconfig VIRTUALIZATION
+	bool "Virtualization"
+	default y
+	---help---
+	  Say Y here to get to see options for using your Linux host to run other
+	  operating systems inside virtual machines (guests).
+	  This option alone does not add any kernel code.
+
+	  If you say N, all options in this submenu will be skipped and disabled.
+
+if VIRTUALIZATION
+
+config KVM
+	tristate "Kernel-based Virtual Machine (KVM) support"
+	depends on HAVE_KVM && EXPERIMENTAL
+	select PREEMPT_NOTIFIERS
+	select ANON_INODES
+	select S390_SWITCH_AMODE
+	select PREEMPT
+	---help---
+	  Support hosting paravirtualized guest machines using the SIE
+	  virtualization capability on the mainframe. This should work
+	  on any 64bit machine.
+
+	  This module provides access to the hardware capabilities through
+	  a character device node named /dev/kvm.
+
+	  To compile this as a module, choose M here: the module
+	  will be called kvm.
+
+	  If unsure, say N.
+
+# OK, it's a little counter-intuitive to do this, but it puts it neatly under
+# the virtualization menu.
+source drivers/virtio/Kconfig
+
+endif # VIRTUALIZATION